It is known to provide a steel shelving unit having a plurality of adjustable shelves, such as shown in U.S. Pat. No. 6,105,513. It is also known to provide a cabinet with steel shelving having a back panel, two side panels, and two door panels mounted on a rigid welded frame. The frame, with the door panels attached to the frame, may be used to retrofit to an existing steel cabinet by mounting the frame with the doors onto the front of the cabinet. With such a prior art system, however, the frame with the attached door panels is shipped to a customer as a large bulky unit. Furthermore, hinges are visible at sides of the frame where the door panels are attached to the frame. Also, the frame must be accurately aligned and welded, and a substantial number of components are required for manufacturing the frame with the attached door panels.
When welding the frame, there is the disadvantage that it is difficult to keep the frame square and true during manufacture.